In recent years, much attention has been focused on the state of the earth's ozone layer. The ozone layer surrounds and protects the earth against harmful ultraviolet radiation. Recently, there have been reports of a marked decrease in the amount of ozone in the earth's atmosphere. Some scientist estimate that as much as 7% of the ozone layer has already been destroyed. Further, researchers have discovered "holes" in the ozone layer. One hole over the continent of Antarctica has an area of more than one million square miles.
The thinning of the earth's ozone layer means that more ultraviolet radiation reaches the earth's surface. The increased exposure to ultraviolet radiation is believed to greatly increase the risk of skin cancer, cataracts, and other illnesses affecting plant and animal life. Certain aliments, such as malignant melanoma, can be life threatening or fatal.
One of the primary causes of ozone depletion is the release of ozone destroying chemicals into the atmosphere. Of most concern are man-made compounds known as chloroflourocarbons (CFC's) and other halogen containing compounds. Chloroflourocarbons are extremely useful for refrigeration and air conditioning systems, as industrial solvents and as foaming agents in the manufacture of plastics. They are also widely used as aerosol propellants. Another useful halogen containing compound is Halon. Halon is widely used in fire extinguishing systems. Halon 1301, for example, is used in fire extinguishing systems for commercial and military aircraft, and is essential to aircraft flight safety.
The universal recognition of the seriousness of the ozone depletion problem has led to international agreements imposing restrictions on the use and manufacture of ozone depleting substances. Current treaty obligations require that the production of ozone destroying chemicals be reduced at least in half by the year 1999. Further, taxation beginning in 1994 of certain ozone depleting substances could render their continued manufacture uneconomical. For example, beginning in 1994, virgin manufacture of Halon 1301 is previously scheduled to be taxed at approximately $26.00 per pound.
These restrictions have made necessary the implementation and design of specialized equipment for the preservation of existing resources of ozone depleting substances used in "essential need" applications. For example, it is essential that the present resource of Halon 1301 from aviation banks be reclaimed, tested and preserved to protect aircraft safety since no other agent in the forseable future will exist to effectively replace Halon 1301.